Such a deal! 165 years ago, Mexico got $10 million and we got Tucson

For all the Tucson haters who wish the city were in a different country, you have Ambassador James Gadsden and the transcontinental railroad to blame.

Gadsden is the architect of the treaty that bears his name, and brought what is now Southern Arizona — including Tucson — and Southwestern New Mexico into the United States.

We bring this up because the treaty was ratified on April 25, 1854, exactly 165 years ago.

Before that treaty, everything south of the Gila River and west of the Rio Grande was more or or less a part of Mexico under another agreement, the Treaty of Guadalupe Hidalgo, which officially ended the U.S. war with Mexico in 1848. 

But that pact left the border, which had not been accurately surveyed and was based on sketchy maps, somewhat vague, with disputed territory in the fertile Mesilla Valley just west of El Paso, and the Santa Rita Mountains south of Tucson, which had rich copper deposits.  

In addition, the U.S. had its eye on a Southern route for a transcontinental railroad. 

Enter Gadsden, a secessionist who had been a U.S. Army lieutenant in the War of 1812 and later became a South Carolina railroad executive who pushed the idea of an uninterrupted rail line through the South, stretching from the Atlantic to the Pacific.

President Franklin Pierce appointed Gadsden as an emissary to Mexico with five offers to present to Mexico that would acquire territory for the railroad. 

Gadsden accomplished his mission. The U.S. got about 30,000 square miles in New Mexico and southern Arizona, including Casa Grande, Yuma, Las Cruces, and yes, Tucson.

MORE: A moving border, and the history of a difficult boundary

In return, Mexico, which was strapped for cash after the war, got $10 million in what came to be known as the Gadsden Purchase, or Venta de La Mesilla (Sale of Mesilla) in Spanish. 

Gadsden, whose grandfather designed the Don't Tread On Me rattlesnake flag in the Revolutionary War, stepped down as emissary to Mexico in 1856 and returned to South Carolina, where he died two years later.

John D'Anna is a reporter with the Arizona Republic and azcentral.com storytelling team. Five generations of his family have called Tucson home, and he'd probably live there now if they had an NHL team. Send story ideas to him at john.danna@arizonarepublic.com and follow him on Twitter @azgreenday. 

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